
package org.odmg;

/**
* The ODMG Set collection interface.
* A <code>DSet</code> object is an unordered collection that does not support
* multiple elements with the same value. An implementation typically is very
* efficient at determining whether the collection contains a particular value.
* <p>
* All of the operations defined by the JavaSoft <code>Set</code>
* interface are supported by an ODMG implementation of <code>DSet</code>,
* the exception <code>UnsupportedOperationException</code> is not thrown when a
* call is made to any of the <code>Set</code> methods.
* @author	David Jordan (as Java Editor of the Object Data Management Group)
* @version ODMG 3.0
*/
// * @see java.lang.UnsupportedOperationException

public interface DSet<E> extends DCollection<E>, java.util.Set<E>
{

/**
* Create a new <code>DSet</code> object that is the set union of this
* <code>DSet</code> object and the set referenced by <code>otherSet</code>.
* @param	otherSet	The other set to be used in the union operation.
* @return	A newly created <code>DSet</code> instance that contains the union of the two sets.
*/
	public DSet<E>			union(DSet<E> otherSet);

/**
* Create a new <code>DSet</code> object that is the set intersection of this
* <code>DSet</code> object and the set referenced by <code>otherSet</code>.
* @param	otherSet	The other set to be used in the intersection operation.
* @return	A newly created <code>DSet</code> instance that contains the
* intersection of the two sets.
*/
	public DSet<E>			intersection(DSet<E> otherSet);

/**
* Create a new <code>DSet</code> object that contains the elements of this
* collection minus the elements in <code>otherSet</code>.
* @param	otherSet	A set containing elements that should not be in the result set.
* @return	A newly created <code>DSet</code> instance that contains the elements
* of this set minus those elements in <code>otherSet</code>.
*/
	public DSet<E>			difference(DSet<E> otherSet);

/**
* Determine whether this set is a subset of the set referenced by <code>otherSet</code>.
* @param	otherSet	Another set.
* @return True if this set is a subset of the set referenced by <code>otherSet</code>,
* otherwise false.
*/
	public boolean	subsetOf(DSet<E> otherSet);

/**
* Determine whether this set is a proper subset of the set referenced by
* <code>otherSet</code>.
* @param	otherSet	Another set.
* @return True if this set is a proper subset of the set referenced by
* <code>otherSet</code>, otherwise false.
*/
	public boolean	properSubsetOf(DSet<E> otherSet);

/**
* Determine whether this set is a superset of the set referenced by <code>otherSet</code>.
* @param	otherSet	Another set.
* @return True if this set is a superset of the set referenced by <code>otherSet</code>,
* otherwise false.
*/
	public boolean	supersetOf(DSet<E> otherSet);

/**
* Determine whether this set is a proper superset of the set referenced by
* <code>otherSet</code>.
* @param	otherSet	Another set.
* @return True if this set is a proper superset of the set referenced by
* <code>otherSet</code>, otherwise false.
*/
	public boolean	properSupersetOf(DSet<E> otherSet);
}

